2. S. angustifolia Engelin. Similar, but distinguished by its narrowly linear 
very acute leaves, somewhat smaller pod, and the quite smooth seed, (8. sylvat- 
ica, vars. angustifolia and linearifolia Muell.)--Ravines of the San Pedro and Rio 
Grande. 
** Annuals: spikes arillary: leaves j-nerved. 
3. S. spinulosa Torr. Low (5 to 15 cm. high), somewhat viscid, dichotomously 
branched, the stems angled and leafy: leaves ovate to lanceolate, acuminate, nar- 
rowed to a broad-winged petiole, ciliate or spinulose-dentate, 2.5 em. long: spikes 
shorter than the leaves, with 1 to 3 pistillate flowers at base: staminate bracts 
minute, 1 flowered; the pistillate with smail glands on long stout pedicels: pod 4 
mm. broad, with a gynophore: seeds oblong-ovate (3 mm. long), smooth, with no 
carunele or a small one, (Sapium(?) annuum Torr. 8, annua Muell.)—Wet ravines 
near Eagle Pass. 
4. S. dentata (Torr), Sessile leaves sharply and sometimes doubly toothed, 
rounded above, cuneate at base, faintly nerved; stipules short, fimbriate: spikes 
terminal, short and slender; bracts very small, ovate, acute, 1-flowered, with short 
stipitate convex glands: pistillate calyx of 3 triangular sepals: pod 4 mm. broad, 
with stout gynophore: seeds 3 mm. long, with conspicuous carunele. (Sapinm anniwn, 
var, dentatum Torr. Sebastiana Treculiana Muell.? Stillingia Torreyana Watson. )— 
Eagle Pass, 
URTICACEA, (Nerrie FAMILY.) 
Herbs, shrubs, and trees, with stipules (often dicecious), moncecious 
or dicecious or rarely (in the Elm family) perfeet flowers furnished with 
a regular calyx and free from the 1 (rarely 2)-celled ovary which forms 
a 1-seeded fruit, and stamens as many as the calyx-lobes (or fewer) and 
opposite them. 
I. Trees, with alternate serrate pinnately-veined leaves and fugacious stipules: flowers 
mostly polygamous, upon the last year’s branches: anthers erect in bud, 
extrorse: styles or stigmas 2: fruit a winged samara or nut-like,—ULME, 
1. Ulmus. Flowers preceding the leaves: ovary 1 or 2-ovuled: fruit winged all 
around. 
2. Planera. Flowers appearing with the leaves: ovule 1: fruit wingless, nut- 
like. 
II. As in I, but the dicecious-polygamous flowers upon branches of the same year: 
fruit a drupe,—CELTIDE.¥. 
3. Celtis. Ovary l-ovuled: flowersappearing with the leaves, which are 3-nerved 
at base. 
UL. Climbing herbs, with watery juice, mostly opposite 3 to 5-lobed leaves, per- 
sistent stipules, and a fibrous inner bark: flowers diwcious, axillary; the 
sterile panicled; the fertile spicate: calyx of one sepal embracing the ovary : 
filaments short, erect in bud: stigmas 2, elongated._-CANNABINE.E. 
4. Humulus. Fertile flowers in asolitary short spike forming a membranaceous 
catkin in fruit: ovary 1-celled, forming a small glandular achene in fruit. 
IV. Trees or shrubs, with milky juice, alternate leaves, and fugacious stipules: 
flowers unisexual, racemose, spicate, or capitate: calyx becoming fleshy or 
juicy in fruit: anthers inflexed in bud: styles undivided or 2-parted, filiform, 
fruit an achene.—MorrE%&. 
5. Ioxylon. Sterile flowers in loose racemes; fertile in globose heads: leaves 
entire. . 
6. Morus. Fertile and sterile flowers in separate spikes: leaves dentate, 3-nerved: 
11874—-No. 3 5 
